cyclohexadecanone

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

For detailed description on the model and its applicability, see attached QMRF and QPRF document.

Principles of method if other than guideline:

Calculation based on KOCWIN v2.00, Estimation Programs Interface Suite™ for Microsoft® Windows v 4.11. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

GLP compliance:

no

Type of method:

other: calculation

Media:

soil

Key result

Type:

log Koc

Value:

3.85 L/kg

Temp.:

25 °C

Remarks on result:

other: Estimate from MCI

Key result

Type:

log Koc

Value:

5.42 L/kg

Temp.:

25 °C

Remarks on result:

other: Estimate from log Kow

Type:

Koc

Value:

7 022 L/kg

Temp.:

25 °C

Remarks on result:

other: Estimate from MCI

Type:

Koc

Value:

262 100 L/kg

Temp.:

25 °C

Remarks on result:

other: Estimate from log Kow

As no single computational model could be identified which would fit completely to the substance, the log Koc of the substance was calculated as the arithmetic mean of the data generated by two individual QSAR approaches. The QSAR model using the log Kow as input parameter was based on the experimentally derived log Kow of 7.77.

 

Method	Type	Value
Estimate from MCI	Log Koc	3.8465
	Koc	7022 L/kg
Estimate from log Kow	Log Koc	5.4185
	Koc	2.621E+05 L/kg
Arithmetic mean	Log Koc	4.6325
	Koc	134561 L/kg

 

The resulting arithmetic mean log Koc was 4.6325 with a corresponding Koc of 134561 L/kg.

Conclusions:

The reliable (Q)SAR prediction resulted in a high adsorption to soil and sediment (log Koc: 3.85 - 5.42; arithmetic mean: 4.63).
Results indicate that the substance is likely to very strongly sorb to soil and sediment particles and show slow to negligible migration to ground water.
The high Koc of 134561 L/kg may reduce the rate of degradation because the substance is less available to microorganisms which is in line with the biodegradation results.

Description of key information

The estimated value for log Koc obtained by (Q)SAR calculations was 5.42 (based on experimental log Kow = 7.77) and 3.85 (MCI method). A mean log Koc of 4.63 with a corresponding KOC of 134561 L/kg was calculated indicating a high potential for adsorption to soil and sediment particles.

Key value for chemical safety assessment

Koc at 20 °C:

134 561

Additional information

There is no experimental study available investigating the adsorption/desorption potential of the test substance to soil and sediment. As no single computational model could be identified which would fit completely to the substance, the log Koc of the substance was calculated as the arithmetic mean of the data generated by two individual QSAR approaches. Therefore, the log Koc was calculated by KOCWIN v2.00 based on the Molecular Connectivity Index (MCI) and based on the measured log Kow. The (Q)SAR calculations resulted in log Koc values of 3.85 (MCI method) and 5.42 (based on experimental log Kow = 7.77). A mean log Koc of 4.63 was calculated indicating a high potential for adsorption to soil and sediment particles.

[LogKoc: 4.63]

[LogKoc: 5.13]